Wednesday, April 9, 2008

That's the word from a new study by the Southern Illinois University School of Dental Medicine that concludes that exposing teeth to soft drinks, even for a short period of time, causes dental erosion--and prolonged exposure can lead to significant loss of tooth enamel. Diet sodas are just as bad for your teeth as sugared sodas. And while non-cola beverages are less acidic than colas, they are particularly nasty on teeth because they are loaded with citric acid, something that is very corrosive to tooth enamel.

Within three minutes of drinking a cola beverage, the potential for dental erosion is 10 times that of fruit juices.

What is dental erosion?

Dental erosion involves loss of tooth structure.

Erosion refers to the action of the acid on the entire surface of the tooth.

Dental erosion and dental cavities are not exactly the same. Cavities and tooth decay tend to be isolated to cavity-prone areas such as in between teeth and in pits and grooves.

The study: Led by Poonam Jain, the researchers measured the acidity or pH level of 20 commercial soft drinks, including Coke, Pepsi, 7-Up and their diet versions, immediately after the cans were opened. Next, slices of enamel from freshly extracted human teeth were weighed before and after being immersed in the soft drinks for 48 hours.

The results: The teeth that were soaked in Coke, Pepsi, RC Cola, Squirt, Surge, 7-Up and Diet 7-Up lost more than 5 percent of their weight, while the remaining sodas created enamel weight losses ranging from 1.6 percent to 5 percent. The most acidic soft drink was RC Cola with a pH of 2.387 (on a scale of 0 to 14 with 0 the most acidic and 14 the least). Cherry Coke's pH was 2.522, followed by Coke at 2.525.

By comparison, battery acid has a pH of 1.0. Pure water at room temperature has a pH of 7.0. "My patients are shocked to hear that many of the soft drinks they consume contain nine to 12 teaspoons of sugar and have an acidity that approaches the level of battery acid," Dr. Kenton Ross, spokesman for the Academy of General Dentistry, explains. "The bottom line is that the acidity in all soft drinks is enough to damage your teeth and should be avoided."

The least damaging soft drink is root beer. Why? It's not carbonated and doesn't contain the phosphoric or citric acids that harm teeth.

So what can you do short of giving up soft drinks entirely? Dr. Ross recommends drinking soft drinks only with meals and use a straw to reduce the soda's contact with the teeth.